The .45 ACP (Automatic Colt Pistol) to be forged in battle. In the late 19th century, the U.S. Army was looking for a round to replace their .38 caliber cartridges. The American pressures needed miscellaneous with an ext stopping power 보다 their conventional issue, and Colt answer the call. The .45 ACP to be designed by smithing legend john Browning in 1904, and it was embraced in 1910 by the U.S. Forces, that also adopted the Colt design 1911 firearm at the time as one official enhancement to the armed forces arsenal, designated M1911. Below we’ll cover all of the essential points of this hugely essential bullet in ourDefinitive .45 ACP Ammo Guide.

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.45 ACP Explained

What does ACP stand for? What does .45 ACP Mean?

.45 ACP

Automatic Colt Pistol was the name offered to the collection of cartridges draft by man Browning in ~ the beginning of the 19th century. There are five ACP cartridges, the biggest of which is the .45 caliber.

A background of the .45 ACP: Invention, initial Use, Adaption

The Philippine-American battle (1899-1902) confirmed that there simply was not sufficient power behind the bullets which were fired in ~ the time. ~ the war was over, the U.S. Army’s Generals go shopping for a brand-new kind of cartridge, one which would certainly be an effective enough to neutralize human being targets top top impact, but little enough to be carried by the usual infantry and also cavalry troops.

John Browning, dad of the .45 ACP

Browning and Colt were trying out with miscellaneous pistol calibers in ~ the time, so once the U.S. Army and also Cavalry inquiry Colt to submit a design for a cartridge in a .45 caliber, Colt amendment its .41 pistol – which to be still in its prototype phase – and also moved on come bigger and much better things v the .45 caliber. The result of this was the .45 ACP cartridge, i beg your pardon Colt submitted for inspection come the military in 1906.

The new round blew the competition away, and also after a series of tests and also trials it was announced together the winner. After several much more modifications were made, at the behest the the U.S. Army, the brand-new and advanced “Cal. .45 automatically Pistol ball Cartridge, design of 1911” was embraced by the military. The M1911 was created until 1970, and also only in 1986 to be the Beretta M9 (9mm) lugged in to change it as the standard U.S. Sidearm. The is one hell the a long run, and it walk to present how efficient the .45 ACP bullet is in combat.

.45 ACP Cartridge Explained

.45 ACP Ammunition

The .45 bullet (11X23mm) is a ring which is accurate and deadly. It come in reasonably heavy loads, due to its size. This is an benefit to some, and a disadvantages to others. It relies on the to plan use, really. The .45 ACP comes in a wide range of weight and also performance levels, so there is a many to occupational around. It’s not a cur and dry sort of situation. The .45 caliber was offered for decades by the military, and for great reason. If it may not be as fast as a 9mm bullet, that hits v a much higher punch.

.45 ACP Ballistics performance Overview

Here is a quick rundown that the ballistic properties of the .45 ACP round, in miscellaneous grain sizes and casings (source: Wikipedia).

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Bullet load / TypeVelocityEnergy
185 grain / bonded Defense1,225 feet every second835 Joules
185 serial / Jacketed hole Point1,050 feet every second614 Joules
200 serial / Jacketed Hollow point +Pressurized1,080 feet every second702 Joules
230 serial / federal Hydra-Shok900 feet every second561 Joules
230 grain / US military Ball full Metal Jacket830 feet every second477 Joules

Ballistics have a much greater impact when you room talking around military uses. In civilian uses, most armed confrontations take place within a distance of 5-10 yards. In ~ those quick ranges, the ballistics don’t do that large of a difference. Ballistics space all around a projectile’s speed, mass, and force. As soon as you are talking around the .45 ACP, you can see that the bigger loads are inherently slower, yet the cartridge is nonetheless effective because of its sheer size.